Delegate
1.基本类:
public class Student { public int Id { get; set; } public string Name { get; set; } public void Study() { Console.WriteLine("学习.net高级班公开课"); } public void StudyAdvanced(string name) { Console.WriteLine("学习.net高级班公开课"); } public static void Show() { Console.WriteLine("); } }
Student
2. 声明委托
public delegate void NoReturnNoPara(); public delegate void NoReturnWithPara(int x, int y); public delegate int WithReturnNoPara(); public delegate string WithReturnWithPara(int x, int y);
3. =+ 的方法
private void DoNothing() { Console.WriteLine("这里是DoNothing"); } private static void DoNothingStatic() { Console.WriteLine("这里是DoNothing"); } private void ShowPlus(int x, int y) { Console.WriteLine("ShowPlus x={0} y={1} x+y={2}", x, y, x + y); } private static void ShowPlusStatic(int x, int y) { Console.WriteLine("ShowPlusStatic x={0} y={1} x+y={2}", x, y, x + y); }
4.委托三部曲
声明(在上面)+实例化+调用
{ NoReturnNoPara method = new NoReturnNoPara(this.DoNothing);//2 委托的实例化 method.Invoke();//3 委托调用 method();//另一种调用方式 //method.BeginInvoke(null, null);//异步调用 this.DoNothing();//直接调用对应的方法,效果一样 }
5.多播委托
{ NoReturnNoPara method = new NoReturnNoPara(MyDelegate.DoNothingStatic); method += student.Study; method -= student2.Study; method += this.DoNothing; method += student.Study; method += Student.Show; method += () => Console.WriteLine("这里lambda"); method.Invoke(); //method.BeginInvoke(null,null);//多播委托不能异步 method -= MyDelegate.DoNothingStatic; method -= MyDelegate.DoNothingStatic; method -= this.DoNothing; method -= student.Study; method -= Student.Show; method -= () => Console.WriteLine("这里lambda"); //委托里面lambda表达式之后加入的方法都无效了? method.Invoke(); } { NoReturnNoPara method = new NoReturnNoPara(student.Study); method.Invoke(); } { NoReturnNoPara method = new NoReturnNoPara(Student.Show); method.Invoke(); } { NoReturnWithPara method = new NoReturnWithPara(ShowPlus); method += ShowPlus; method += ShowPlus; method += ShowPlus; method -= ShowPlus; method -= ShowPlus; method(, ); }
Event
public class Baby { public void Cry() { Console.WriteLine("{0} Cry", this.GetType().Name); } }
Baby
public class Brother { public void Turn() { Console.WriteLine("{0} Turn", this.GetType().Name); } }
Brother
public class Dog { public void Wang() { Console.WriteLine("{0} Wang", this.GetType().Name); } }
Dog
public class Father { public void Shout() { Console.WriteLine("{0} Shout", this.GetType().Name); } }
Father
public class Mother { public void Wispher() { Console.WriteLine("{0} Wispher", this.GetType().Name); } }
Mother
public class Mouse { public void Run() { Console.WriteLine("{0} Run", this.GetType().Name); } }
Mouse
public class Neighbor { public void Awake() { Console.WriteLine("{0} Awake", this.GetType().Name); } }
Neighbor
public class Stealer { public void Hide() { Console.WriteLine("{0} Hide", this.GetType().Name); } }
Stealer
发布
/// <summary> /// 发布者 /// 一只猫,miao一声 /// 导致一系列的触发动作 /// </summary> public class Cat { public void Miao() { Console.WriteLine("{0} Miao", this.GetType().Name); new Neighbor().Awake(); new Mouse().Run(); new Dog().Wang(); new Baby().Cry(); new Mother().Wispher(); new Brother().Turn(); new Father().Shout(); } public Action MiaoAction;//委托的实例 public event Action MiaoActionEvent;//事件是 委托的实例,加了event关键字-----发布者 //event做了权限控制,保证外部不能赋值和调用 public void MiaoDelegate() { Console.WriteLine("{0} MiaoDelegate", this.GetType().Name); MiaoAction.Invoke(); } public void MiaoEvent() { Console.WriteLine("{0} MiaoEvent", this.GetType().Name); if (MiaoActionEvent != null) { //MiaoActionEvent.Invoke(); //MiaoActionEvent(); foreach (Action item in MiaoActionEvent.GetInvocationList())//触发 { Console.WriteLine("*********"); item.Invoke(); //item.BeginInvoke(null,null); } } } }
订阅:
{ Console.WriteLine("*******Miao******"); Cat cat = new Cat(); cat.Miao(); Console.WriteLine("*******MiaoDelegate******"); //cat.MiaoAction += new Neighbor().Awake; cat.MiaoAction += new Mouse().Run; cat.MiaoAction -= new Mouse().Run; cat.MiaoAction += new Baby().Cry; cat.MiaoAction += new Mother().Wispher; cat.MiaoAction.Invoke(); cat.MiaoAction = null; cat.MiaoAction += new Brother().Turn; cat.MiaoAction += new Father().Shout; cat.MiaoAction += new Dog().Wang; cat.MiaoDelegate(); Console.WriteLine("*******MiaoEvent******"); cat.MiaoActionEvent += new Neighbor().Awake; cat.MiaoActionEvent += new Mouse().Run; cat.MiaoActionEvent += new Baby().Cry; //cat.MiaoActionEvent.Invoke(); //cat.MiaoActionEvent = null; cat.MiaoActionEvent += new Mother().Wispher; cat.MiaoActionEvent += new Brother().Turn; cat.MiaoActionEvent += new Father().Shout; cat.MiaoActionEvent += new Dog().Wang; cat.MiaoEvent(); }